茶多酚对β-淀粉样蛋白25-35肽段诱导红细胞溶血的影响  

The Influence of Tea Catechins to the Hemolysis Induced by Amyloid-β Peptide 25-35 Fragment

作　　者：张建红[1] 王一敏[1] 严向阳[1] 曾成鸣[1] 

机构地区：[1]陕西师范大学生命科学学院教育部药用植物资源和天然药物化学重点实验室,西安710062

出　　处：《天然产物研究与开发》2008年第3期537-539,573,共4页Natural Product Research and Development

摘　　要：β-淀粉样蛋白在神经组织中聚集被认为与Alzheimer’s疾病密切相关,一些天然多酚化合物证实可抑制蛋白质的淀粉样聚集。本文采用β-淀粉样蛋白25-35肽段诱导人红细胞溶血为实验模型,检测几种结构相似的茶多酚化合物对β-淀粉样蛋白诱导细胞损害的影响。结果表明,表没食子儿茶素没食子酸酯(EGCG)可以抑制β-淀粉样肽导致的溶血,而表儿茶素没食子酸酯(ECG)则可以促进溶血。两者在结构上仅在B环上相差一个羟基。这种对溶血作用的差异可能来源于对金属离子螯合能力的差异。一种铁离子的强力螯合剂甲磺酸去铁胺可抑制ECG的促溶血作用,说明体系中的微量铁离子可能是ECG促多肽溶血过程中的一个重要因素,同时也表明β-淀粉样蛋白诱导细胞损害与金属离子介导的氧化还原作用有关。The fibriUar aggregation of amyloid-β peptide in neural tissue is a hallmark of Alzheimer＇ s disease. Some natural polyphenolie compounds were reported to be able to inhibit the formation of amyloid fibrils. In this study,tea catechins with similar molecular structures were tested in their effects on hemolysis induced by Aβ25-35, a fragment derived from amyloid-β peptide. The results showed that epigallocateehin gallate （EGCG） inhibited strongly Aβ-induced hemolysis;whereas epieateehin gallate （ECG）, with one less hydroxyl group on B-ring, had a reverse action. Deferoxamine mesylate, one of the strongest chelators for iron ion, suppressed efficiently the ECG-promoted hemolysis, indicated that trace iron played a role in this process. On the basis of this result,we suggest herein that the eeUular damages induced by amyloid-β peptide are related to redox reaction mediated by metal ions.

关 键 词：Β-淀粉样蛋白 红细胞 溶血 茶多酚 甲磺酸去铁胺 

分 类 号：R992[医药卫生—毒理学] Q949.64[医药卫生—药学]